Fixed regression where the :func:`_sql.select` construct would not be able
to render if it were given no columns and then used in the context of an
EXISTS, raising an internal exception instead. While an empty "SELECT" is
not typically valid SQL, in the context of EXISTS databases such as
PostgreSQL allow it, and in any case the condition now no longer raises
an internal exception.

For this case, also add an extra whitespace trim step for the unusual
case that there are no columns to render.  This is done in such a
way as to not interfere with other test cases that are involving
custom compilation schemes.

Fixes: #9440
Change-Id: If65ba9ce15d371f09b4342ad0669143b7b082a78

Added a full suite of new SQL bitwise operators, for performing
database-side bitwise expressions on appropriate data values such as
integers, bit-strings, and similar. Pull request courtesy Yegor Statkevich.

Fixes: #8780
Closes: #9204
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/9204
Pull-request-sha: a4541772a6a784f9161ad78ef84d2ea7a62fa8de

Change-Id: I4c70e80f9548dcc1b4e3dccd71bd59d51d3ed46e

Fixed regression related to the implementation for the new
"insertmanyvalues" feature where an internal ``TypeError`` would occur in
arrangements where a :func:`_sql.insert` would be referred towards inside
of another :func:`_sql.insert` via a CTE; made additional repairs for this
use case for positional dialects such as asyncpg when using
"insertmanyvalues".

at the core here is a change to positional insertmanyvalues
where we now get exactly the positions for the "manyvalues" within
the larger list, allowing non-"manyvalues" on the left and right
sides at the same time, not assuming anything about how RETURNING
renders etc., since CTEs are in the mix also.

Fixes: #9173
Change-Id: I5ff071fbef0d92a2d6046b9c4e609bb008438afd

Change-Id: I625af65b3fb1815b1af17dc2ef47dd697fdc3fb1

it's hoped for 2.0.0 final to be next, in early January

Change-Id: If4285f0929f4a2895f2bc93d9e8336599b973bcf

Added test support to ensure that all compiler ``visit_xyz()`` methods
across all :class:`.Compiler` implementations in SQLAlchemy accept a
``**kw`` parameter, so that all compilers accept additional keyword
arguments under all circumstances.

Fixes: #8988
Change-Id: I1cefc313e4e64a10ee7dd14400137fbe02ce9523

To accommodate for third party dialects with different character escaping
needs regarding bound parameters, the system by which SQLAlchemy "escapes"
(i.e., replaces with another character in its place) special characters in
bound parameter names has been made extensible for third party dialects,
using the :attr:`.SQLCompiler.bindname_escape_chars` dictionary which can
be overridden at the class declaration level on any :class:`.SQLCompiler`
subclass. As part of this change, also added the dot ``"."`` as a default
"escaped" character.

Fixes: #8994
Change-Id: I52fbbfa8c64497b123f57327113df3f022bd1419

Fixed bug where SQL compilation would fail to make use of
:meth:`_types.TypeEngine.bind_expression` on a given type when used in the
context of an "expanding" (i.e. "IN") parameter with the ``literal_binds``
compiler parameter in use.

Fixes: #8989
Change-Id: Ic9fd27b46381b488117295ea5a492d8fc158e39f

The :meth:`.SQLCompiler.construct_params` method, as well as the
:attr:`.SQLCompiler.params` accessor, will now return the
exact parameters that correspond to a compiled statement that used
the ``render_postcompile`` parameter to compile.   Previously,
the method returned a parameter structure that by itself didn't correspond
to either the original parameters or the expanded ones.

Passing a new dictionary of parameters to
:meth:`.SQLCompiler.construct_params` for a :class:`.SQLCompiler` that was
constructed with ``render_postcompile`` is now disallowed; instead, to make
a new SQL string and parameter set for an alternate set of parameters, a
new method :meth:`.SQLCompiler.construct_expanded_state` is added which
will produce a new expanded form for the given parameter set, using the
:class:`.ExpandedState` container which includes a new SQL statement
and new parameter dictionary, as well as a positional parameter tuple.

Fixes: #6114
Change-Id: I9874905bb90f86799b82b244d57369558b18fd93